Hi,

I now something to the manual, NEWS and changed the doc string + commit msg as advised. I decided on defcustom in the end because this way it is easy for the user to figure out what goes wrong in case he/she modifies grep-command and highlighting is missing. Hope that is fine.

Pls let me know if there is anything else I need to change.

Thanks!

________________________________________
From: Eli Zaretskii <eliz@gnu.org>
Sent: 09 June 2020 15:43
To: Basil L. Contovounesios
Cc: Simon.lang@outlook.com; 41766@debbugs.gnu.org; dgutov@yandex.ru; juri@linkov.net
Subject: Re: bug#41766: Make it possible to change regexp to identify and highlight grep matches via customization

> From: "Basil L. Contovounesios" <contovob@tcd.ie>
> Date: Tue, 09 Jun 2020 12:55:25 +0100
> Cc: "41766@debbugs.gnu.org" <41766@debbugs.gnu.org>,
>  Dmitry Gutov <dgutov@yandex.ru>, Juri Linkov <juri@linkov.net>
>
> I wonder, though: the default value matches some quite obscure codes
> which aren't (and maybe shouldn't be) documented, so is a defcustom
> really suitable for this?

They are SGR escape sequences that Grep emits to color its output.  We
should probably mention that in the doc string.